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本英文版为内部资料,仅供参考,以中文版为准。
Industrial Standard of People's Republic of China
中华人民共和国行业标准
Steel Pipe Flanges for
Petrochemical Industry
石油化工钢制管法兰
SH 3406-96
Prepared by: Beijing Petrochemical Engineering Corp. of SINOPEC
Approved by: China Petrochemical Engineering Corporation (SINOPEC)
1996 Beijing
1. Scope of application
This standard is applicable to flanges and blind flanges for steel pipes of piping works in petrochemical enterprises.
2. Reference standards
GB711
Hot rolled quality carbon structural steel plates and wide strips
GB3274
Hot-rolled steel plates for ordinary carbon structural steel and low alloy structural steel Technical conditions
GB3531
Technical conditions for low alloy steel plates for low temperature pressure vessels
GB4237
Hot rolled stainless steel sheets and plates
GB7306
Pipe thread sealed by thread
JB4726
Carbon steel and low alloy steel forgings for pressure vessels
JB4727
Carbon steel and low alloy steel forgings for low temperature pressure vessels
JB4728
Stainless steel forgings for pressure vessels
SH3405
Series of steel pipe size for petrochemical enterprise
3. General provisions
Nominal diameter
There are 33 nominal diameters DN for flanges as follows:
15
20
25
(32)
40
50
(65)
80
100
(125)
150
220
250
300
350
400
450
500
550
600
650
700
(750)
800
(850)
900
(950)
1000
(1100)
1200
(1300)
(1400)
(1500)
The sizes with brackets are not mended.
Nominal pressure
The nominal pressure of flanges are in eight grades of , , , , , , and , and the nominal diameter size ranges of each nominal pressure grade are shown in Table 3 – 1.
Table 3 – 1 Nominal diameter size ranges of each nominal pressure grade
Nominal pressure
PN (MPa)
Nominal diameter DN (mm)
15~300
350~600
650~1500